Facebook on Thursday rolled out new features to help combat a rash of fake stories being shared on its news feed, following fierce debate around the world’s largest social network’s role in spreading false information.

The new features, available for the time being only to select users in the United States, add options for readers and third-party fact checkers to flag suspect articles and tweak Facebook’s algorithms, and provide more restrictions on advertising.

In China, where online content has for years been subject to strict controls, Chinese social networks have developed sophisticated systems to combat what authorities describe as “online rumours”.

We look at some of the ways China’s social media sites tackle false information being shared across a vast country with 700 million internet users.

How does Weibo, China’s version of Twitter, address fake news?

Similar to the new function unveiled by Facebook, Weibo users can report a hoax by clicking the upper right hand corner of a post. A team at Weibo will then examine the post if it has been reposted for more than 100 times or has been reported by more than 10 users.

Posts that are “obviously untrue” will be marked as such.

In some cases, those who are for and against the content are allowed 24 hours to submit evidence, during which the post is marked as “under debate”. An “expert committee” later makes a final decision on the post’s truthfulness based on the evidence.

Users who post false rumours will be banned from posting for up to 30 days depending on the number of reposts. An account will be suspended if a user posts fake content five or more times in a three-month period.

Every Weibo user has a credibility score and points are deducted if the user posts rumours, or abuses or harasses other users. Accounts are marked as “not credible” for having a low score and users can be banned.

What about the instant-messaging app WeChat?

WeChat users can report other users for sharing false information by clicking a button on the profile page. They can also report an entire chat group for harassment or gambling.

Users can also report suspect articles and websites shared by their friends on WeChat Moments. The reports are then examined by employees at Wechat.

The platform keeps a database of fake news, so similar content can be blocked automatically if reposted in the future.

Last year, a security officer at WeChat said the platform receives more than 30,000 fake news reports a day, and an average of 2.1 million false rumour posts were blocked by the system every day, according to the Southern Metropolis Daily.

In November, WeChat public channel News Breakfast was banned from posting for seven days after reports from users that it was publishing fake news.

One article flagged as being misleading claimed some cheap roast duck on the market was from sick ducks and contained hazardous chemicals, according to a statement from WeChat.

How do these efforts differ from those taken by Facebook?

China imposes strict control on online speech and internet companies work hand-in-hand with the government to address fake news.

In May, for example, Weibo and the Ministry of Public Security jointly launched a national online platform to combat rumours. Employees at Weibo filter and group the reports from users and send them to China’s internet police for examination.

After false information is identified, the police will inform the public through their Weibo accounts. They can also take legal action to punish the publishers if the fake information has caused “serious consequences”.

Local internet authorities also frequently shut down WeChat public channels that they say have been used to spread false rumours.

In 2013, China’s top court said people would be charged with defamation if false rumours they shared online were viewed by 5,000 internet users or reposted more than 500 times.

Is it only fake news?

Social media users must follow the “nine don’ts and seven bottom lines” set out in China’s internet regulations.

According to the regulation, websites may not carry any content that hurts national unity, provokes ethnic tension or promotes superstition.

The government often cites the regulation in cracking down on online dissidence.

In October 2016, internet watchdogs and mainland websites recorded 2.56 million “effective reports” on illegal information, official data showed.

About 60 per cent of the reports were about obscene content, and 13.1 per cent were “politically harmful information”.

China’s powerful internet censors also keep a close eye on everything that is published online, even content that has not been reported as suspect.

Authorities remove large numbers of articles and websites from cyberspace every year without informing the publishers or readers.